Pressure sensitive adhesives have enjoyed great acceptance for their convenience of use. The pressure sensitive adhesive is often used for films and articles containing graphic images. The advantages of the pressure sensitive adhesives are their strong bonding and simplicity of application. Pressure sensitive adhesives typically have a relatively high strength and high initial bonding tenacity. The positioning of the product must be precise because of the adhesive's initial strong bond. To reposition the adhesive, the portion of the article adhered to the substrate must be pulled from the substrate, which may result in the adhesive article being deformed, torn, wrinkled, creased, or the like. Attempts have been made to make adhesive articles repositionable and/or slideable. A product may be considered repositionable where the product may be removed after light application of pressure without destroying the product or the substrate. Slideability allows for correction of alignment of the adhesive article without the need of completely removing the article and possibly destroying the adhesive article or the substrate. For example, stand-offs and areas of non-adhesive material have been used to reduce the initial tenacity of an adhesive surface.
Adhesive articles may also be prone to trapping air under the product and forming bubbles or wrinkles when the article is applied to a substrate. Air egress may be referred to as the ability of the product to provide a route for air trapped under the product to be removed.
Generally, two separate systems are required to provide an adhesive article with both air egress and repositioning characteristics. That is, to exhibit both characteristics, an adhesive article must include a first system to provide repositionability and a second system to provide air egress. For example, areas of non-adhesive material may be used to provide repositionability and/or slideability. Air egress is typically provided by a groove or recessed area embossed in the surface of the adhesive layer.